[purplepuller]

Boiled pass. side battery last Wednesday when hauling wife's horse to be reshod. Replaced batteries and volt meter showed over charging and the rail pressure gauge was bouncing all over the place While driving home. Truck even surged when pulling some hills. Finally was able to check things out this evening, cleaned all connections and grounds. Checked connection on FCA wiggled it a little bit to make sure good connection. Started truck up and the rail pressure was pegged and truck was idling rough. Shut truck off and wiggled wires on FCA and started truck and all was fine. Could FCA be bad or connection be bad. Wire from alternator to battery looks bad, is it a special wire or what size is wire to make and replace.

 

[tryNto]

Bad connection on FCA.
The wire from the alternator is just wire, I'm not sure what's on there.
It ok to go larger but not smaller.

 

[evildiesel]

Boiled pass battery is due to a bad cross over cable. It goes from battery positive to battery positive.

The FRP pegging is due to a bad connection at the FCA. Could be the terminals aren’t tight enough anymore, could be a bad wire.

 

[purplepuller]

Boiled pass battery is due to a bad cross over cable. It goes from battery positive to battery positive.

The FRP pegging is due to a bad connection at the FCA. Could be the terminals aren’t tight enough anymore, could be a bad wire.

Cross over cable replaced with new factory cable 2 years ago. After cleaning all connections on batteries and grounds, truck running with volt meter it showed 14.8 on both batteries and wire from alt. to pass. battery was warm. Will check wires on connection on FCA. Trucks not a DD and sits a lot, found muddy squirrel or chipmunk or mice tracks on valve cover and intake. Did look at wires over really good, didn't see any chew marks. Can a person buy a new connector for FCA?

 

[evildiesel]

Yes you can either get one here

https://graysperformance.com/collec...ails/products/cummins-fca-connector-2003-2018

Or go to your dealer and order this part number

05143779AB

 

[purplepuller]

Replace FCA( From Geno's and cummins part) and replaced connector with factory piece. took care of bouncing of RP. Took it for a test drive and looks normal on RP.:thumbup:

 

[evildiesel]

Thanks for the update! Glad to hear it sounds like you got it fixed up

 

[tryNto]

:agree2: Thanks for posting the fix.

 

[Gone Johnson]

It sounds like you found your problem, but I thought I'd add my two cents for helping other people that find this thread diagnose their problems in the future if the previous suggestions didn't work.

The only batteries I've ever seen boiled was caused by a heavy duty winch cable added to the back of an alternator. The cable was poorly routed, and the vibration had worn through the insulation. This short caused the voltage regulator to think the batteries needed charged really badly. It fried the batteries and the alternator. Probably not that useful of advice in most cases, but if you have a boiling battery problem it might be worth going over the non-fused cables with a fine tooth comb if the previous suggestions didn't solve the problem.

 

[purplepuller]

Well problems again, Since it turned colder this last few weeks truck is overcharging. Waiting on Battery Temp Sensor to replace. With top of line voltmeter both batteries show voltage while running. Same reading from positive post to body ground both sides. 15.5 to 15.8 is the reading. A couple of times after truck warms up and shut down for about ten minutes or so start up and all is fine. Also when overcharging the FP is about 300 to 500 lbs higher when overcharging like at idle it shows 10000. Then last night when to town( 25 degrees outside) truck warmed up fine. Still overcharged. Set for about 2 1/2 hours. Started home with and check gauges come on and voltmeter on dash showed 10 volts, but went off when started charging again. But was overcharging. New Batteries all connections cleaned, and both batteries show same voltage. I'm stumped and frustrated. Hoping BTS takes care of problem if not might have to get computer flashed.

 

[ssteve]

From what I've read and experienced sounds about normal. Others will chime in, but colder weather batteries will charge at a slightly higher voltage. My truck, in colder weather will go to 1000 rpm when first started and the batteries are a little cold and undercharged. Don't know if the ECM is compensating for the draw that the grid heater puts on the system or not.
Batteries not charging and check engine lights are not normal, check again for loose connections and grid heater solenoid sticking on, or positive wire rubbed through to ground.

 

[BR3500]

Try testing the batt sensor. Pull it from the tray and disconnect the wiring plug. Measure the resistance in ohm across the sensor terminals. Resistance should be between 300 and 90K ohms. If outside that range, replace the sensor. Did you replace the cross over cable? If voltage drop across the cable is above 0.3 VDC, replace the cable. Ideally, lower than 0.1 VDC is the mark to be at. Are you throwing any codes for batt sensor performance (P0514, 0516 or 0517)?

 

[purplepuller]

Forgot to mention that CEL was on. Always comes on after towing wife's horse there last Thursday 1740 It always does that because I have lock up switch and use it a few times and have 2503 which is low voltage, which happened last night. Crossover cable replaced Jan. 2016 with new factory.

 

[rghavana]

p2503

Possible Causes
OTHER DTC’S PRESENT
GENERATOR
ECM
INTERMITTENT CONDITION

check for other codes, don't always throw MIL
check wires/conections including grounds to batteries , ECM , and alternator including grounds.

Generator
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the generator field terminals at the generator.
Is the resistance between .5 and 15 Ohms?
No >> Replace the generator.

FIELD DRIVER CIRCUIT SHORTED TO GROUND
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the generator field driver circuit between the
generator and battery negative.
Is the resistance greater than 100 ohms?
Yes >> Go To 4
No >> Repair the generator field driver circuit shorted to ground

ECM
Measure and record the voltage between battery positive circuit of the ECM harness connector and the battery negative circuits of the ECM harness connector.
Reconnect the ECM connectors.
Use the scan tool to measure and record battery voltage.
Compare the voltage reading from the voltmeter with that of the scan tool.
Are the readings within 3 volts of each other?
Yes >> Refer to the INTERMITTENT CONDITION Symptom (Diagnostic
Procedure). (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No >> Replace and program the ECM in accordance with the Service
Information.

 

[purplepuller]

Ok when checking of ohms, batteries hooked up or unhooked. Not the best on the electrical stuff.

 

[BR3500]

Resistance is always checked with power disconnected from the circuit under test. Also, key should be in the off position. First resistance test is done with the harness disconnected and meter probes attached to the generator terminals. The second resistance test (for the field driver) is done with one meter probe inserted into cavity 2 (connector should be marked or labeled with circuit position number) of the generator wiring plug and the other probe in contact with the negative battery terminal. I'd measure the resistance at both negative terminals and compare the 2. They should be really close in value assuming the wiring and ground connections are well made. Be really careful with the connectors and terminals and don't try and jamb a huge meter probe tip into any of the wiring connector/cavity holes. If not careful, you'll probably damage the terminal cavity that holds the pin stationary inside the connector body and this can lead to lose connections.

 

[purplepuller]

OK finally got to check out truck today. This is what I found, according to test on alternator It showed 3.3 ohms. So that means alternator is bad.

 

[rghavana]

OK finally got to check out truck today. This is what I found, according to test on alternator It showed 3.3 ohms. So that means alternator is bad.

Generator
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the generator field terminals at the generator.
Is the resistance between .5 and 15 Ohms?

"3.3 ohms" you measured is between .5 ohms and 15 ohms so generator good, so far ( no internal resistance in it).

so zero your meter and on to next test
FIELD DRIVER CIRCUIT SHORTED TO GROUND
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the generator field driver circuit between the
generator and battery negative.
Is the resistance greater than 100 ohms?
Yes >> Go To ECM test
No >> Repair the generator field driver circuit shorted to ground

then ECM test but i like to see .1-.2 volts, for voltage drop for ecm controlled vehicles.

Measure and record the voltage between battery positive circuit of the ECM harness connector and the battery negative circuits of the ECM harness connector.
Reconnect the ECM connectors.
Use the scan tool to measure and record battery voltage.
Compare the voltage reading from the voltmeter with that of the scan tool.
Are the readings within 3 volts of each other?
Yes >> Refer to the INTERMITTENT CONDITION Symptom (Diagnostic
Procedure). (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No >> Replace and program the ECM in accordance with the Service
Information.

 

[purplepuller]

Did other test and OK on it. Put Alt. Back in and installed new wire from Alt to battery. Got it from Custom Battery Cables. Drove it today for a couple of hours, all seems well. :confused013:

 

[steelhead1]

Alternator is connected directy to the passenger side batt. Charging sticks on, passenger battery boils over spraying corrosive sulfuric acid all over the passenger side of engine bay. Crossover is most likely ate up under insulation.

Clean and scrub down all on passenger side with battery acid neutralizer or plain old baking soda mixed with distilled water. Lots of chemicals in tap well water. I've seen the eat out Cummins motors mounts and frame, Cummins fall out of Rams. If left on the wiring loom and connectors, expect to pay a Dodge electrical systems tech about 10 Ben Franklins